package 事物操作;


import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;
import java.sql.Statement;

/*
* 转账：A给B转5k
* */
public class Transaction {
    public static void main(String[] args)  throws Exception{
        String url = "jdbc:mysql://10.4.43.109/db_jdbc_demo?characterEncoding=utf8&useSSL=false&serverTimezone=UTC";
        String user = "root";
        String pass = "000000";
        Connection conn = null;
        Statement stmt = null;
//        ResultSet省略,因为Update没有结果集

        try{
            Class.forName("com.mysql.jdbc.Driver");
            conn = DriverManager.getConnection(url,user,pass);
            String sql1 = "update t_account set money = money - 5000 where id = 1";
            String sql2 = "update t_account set money = money + 5000 where id = 2";
//            开启事物
            conn.setAutoCommit(false);
            stmt = conn.createStatement();
            int i = stmt.executeUpdate(sql1);
            int j = stmt.executeUpdate(sql2);
            if (i+j==2){
                System.out.println("转账成功");
                conn.commit();
            }else{
                System.out.println("转账失败");
            }
        }catch (Exception e){
            e.printStackTrace();
            System.out.println("转账出现异常");
            try{
                conn.rollback();
            }catch (SQLException ex){
                ex.printStackTrace();
            }
        }finally {
            try {
                stmt.close();
                conn.close();
            }catch (SQLException e){
                e.printStackTrace();
            }
        }
    }
}
